Physics: Magnetism 2
Overview
Pupils will develop an appreciation of how electricity and magnetism are closely linked, by looking at processes such as the Motor and Generator Effect. They will learn how magnetism is used to record and listen to music, and how “Energy Resources” actually create electrical current. Pupils should also review the keywords from the previous Year 8 Magnetism topic.
The main SMSC/Personal Development content of this topic includes: PD2 – Developing and deepening pupils’ understanding of mutual respect and tolerance (team and or group work).
PD16 – Use of imagination and creativity in their learning.
The main UN Rights of a Child covered are No. 2 – No discrimination and No. 13 – Sharing thoughts freely
Example Key Words
Induced
Unlike a permanent magnet, an induced magnet only becomes a magnet when it is placed in a magnetic field. The induced magnetism is quickly lost when the magnet is removed from the magnetic field.
Motor Effect
A wire carrying a current creates a magnetic field. This can interact with another magnetic field, causing a force that pushes the wire at right angles. This is called the motor effect.
Generator Effcet
A potential difference can be induced (created) in a conductor when there is movement between the conductor and a magnetic field. This is called electromagnetic induction and is often referred to as the generator effect.
Alternator /Dynamo
An alternating current (AC) generator (or alternator) is a device that produces an alternating potential difference. A dyanmo is a is another device that produces a potential difference, which is DC.
Transformer
Transformers are used to increase or decrease the potential difference of alternating currents. A transformer consists of two coils of wire wound on a metal core.